The Prime Minister will today brand plastic waste "one of the great environmental scourges of our time" and lay out hopes to dramatically reduce it by 2042.

Alongside the plan for supermarkets, the Government will use UK aid money to help developing nations reduce their own waste and will pump cash into plastics innovation.

It will also extend the 5p charge for plastic bags in England to all shops - something already practised in Scotland - and look at taxing single-use plastic items like takeaway boxes and coffee cups.

In a speech in London to launch the landmark drive, May will say: "I think people will be shocked at how today we allow so much plastic to be produced needlessly."

And she will add: "We look back in horror at some of the damage done to our environment in the past and wonder how anyone could have thought that, for example, dumping toxic chemicals into rivers was ever the right thing to do."

But a string of green groups attacked what they called "woolly" government promises and argued the plans have no legal bite.

Labour meanwhile said the plans were a "cynical attempt at rebranding the Tories' image" while the Liberal Democrats said the 24-year target to remove plastic waste was too long.

The number of single use plastic products being found washed up on beaches is rising, which has led to calls for a crackdown in the products.

Scotland's Environment Secretary Roseanna Cunningham said: "Banning plastic cotton buds would be a clear sign of our ambition to address marine plastics and demonstrate further leadership on this issue.

"Despite various campaigns, people are continuing to flush litter down their toilets and this has to stop.

"Scotland's sewerage infrastructure collects and treats some 945 million litres of waste water each day. These systems are not designed to remove small plastic items such as plastic buds which can kill marine animals and birds that swallow them."

Major retailers have switched to paper cotton buds in recent years, but cheap plastic products are still widely available.

Skye, Lochaber and Badenoch MSP Kate Forbes has also been campaigning to crack down on the use of plastic straws.